2. Use commas to bracket nonrestrictive phrases, which are not essential to the sentence/'s meaning.

　　3. Do not use commas to bracket phrases that are essential to a sentence/'s meaning.

　　4. When beginning a sentence with an introductory phrase, include a comma.

　　5. To indicate possession, end a singular noun with an apostrophe followed by an /"s/". Otherwise, the noun/'s form seems plural.

　　6. Use proper punctuation to integrate a quotation into a sentence. If the introductory material is an independent clause, add the quotation after a colon. If the introductory material ends in /"thinks,/" /"saying,/" or some other verb indicating expression, use a comma.

　　7. Make the subject and verb agree with each other, not with a word that comes between them.

　　8. Be sure that a pronoun, a participial phrase, or an appositive refers clearly to the proper subject.

　　9. Use parallel construction to make a strong point and create a smooth flow.

　　10. Use the active voice unless you specifically need to use the passive.

　　11. Omit unnecessary words.

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